A collaborative linkage study of breast cancer families that are not segregating mutations at either the BRCA1 or BRCA2 loci is ongoing. Collaborators in Finland, Sweden and Iceland are working together with NHGRI to add more families to the data set. Genotyping of several candidate regions and a genome wide scan have been performed on these samples. Linkage analysis is ongoing and a paper is in preparation. Fine mapping of positive regions is also ongoing. - breast cancer, linkage, genetics, mapping, susceptibility - Human Subjects